Biosynthesis of porphyrins and related macrocycles. Part 13. Structure of the protoporphyrin isomer derived from coproporphyrinogen IV by the action of beef-liver coproporphyrinogenase : synthesis of protoporphyrin XIII

Abstract

Coproporphyrinogen IV (8) is synthesised and is oxidatively decarboxylated by coproporphyrinogenase from beef-liver to produce, after aromatisation, a porphyrin proved to be protoporphyrin XIII (11) by spectroscopy and by unambiguous synthesis; the synthetic route is described. A monovinylporphyrin, derived from an intermediate for the conversion (8)→(11), is also isolated. The importance of these results for earlier biosynthetic studies with pyrromethanes is discussed.